Liquid anionic-dialkylolamide

ABSTRACT

Dialkylolamides of fatty acids which contain 10 to 14 carbon atoms are prepared by condensing fatty acylating compounds such as the acid, its ester, acid anhydride or acyl halide with a dialkylolamine, the latter reactant being preferably in excess. Suitable molar ratios of acylating compound to dialkylolamine lie bebetween 1 : 1 and 1 : 10, preferably about 1 : 2 to about 1 : 3, the reaction being carried out between about 100 DEG  C. and about 200 DEG  C.  A complex mixture of products is formed, and in order to obtain an equilibrium mixture containing an effective proportion of the dialkylolamide the product may be cooled relatively slowly or held at a slightly elevated temperature for a period of time. A typical reaction mixture from lauric acid (90 per cent pure) and diethanolamine may contain 65 per cent diethanolamide, 10 per cent diethanolamine soap and 25 per cent diethanol-piperazine and other substances including water.  The fatty acylating substances may be derived from pure, impure or mixtures of capric, lauric, and myristic acids.  Mixtures of these acids derived from natural sources and containing acids of higher and lower molecular weight may also be used, such as &#34;topped&#34; coconut oil fatty acids. Suitable dialkylolamines for the reaction include, besides diethanolamine, N,N - bis - (2,3 - dihydroxypropyl) - amine, dipropanolamine, N,N - bis - (2-hydroxylpropyl) - amine and dibutanolamine.  Dialkylolamides specified include N,N-bis-(2-hydroxyethyl) - lauramide, N,N - bis - (2-hydroxyethyl) - capramide, N,N - bis - (2-hydroxyethyl) - myristamide, N,N - bis - (2,3-dihydroxypropyl) - lauramide, N,N - bis - (2,3-dihydroxypropyl) - myristamide, N,N - bis - (3-hydroxypropyl) - lauramide, N,N - bis - (3-hydroxypropyl) - capramide, N,N - bis - (2-hydroxypropyl) - myristamide, and N,N - bis-(4-hydroxybutyl)-lauramide.  The dialkylolamides may be incorporated in detergent compositions (see Group III).ALSO:A liquid detergent composition comprises a water-soluble anionic sulphated or sulphonated detergent containing an aliphatic chain of at least 8 carbon atoms, a dialkylolamide of a fatty acid which contains 10 to 14 carbon atoms and a solvent for the detergent and the dialkylolamide.  Suitable solvents include the low molecular weight hydroxyl containing solvents, particularly water, saturated aliphatic alcohols or aqueous saturated aliphatic alcohols. Specified alcohols include ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, ethylene glycol, propylene glycol, glycerol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether.  Dioxan may also be used.  It is preferred to use water, mono- or di-hydric alcohols containing 2 to 4 carbon atoms in the molecule, lower (i.e. C1-C5) alkyl ethers of these dihydric alcohols and mixtures of these solvents The dialkylolamide may be of general formula RCO-NR1R11, where RCO represents a fatty acyl radical containing 10 to 14 carbon atoms and R1 and R11 are the same or different hydroxyalkyl groups of 1-5 carbon atoms.  These hydroxyalkyl groups may be mono-or polyhydroxy in character. Specific dialkylolamide additives include N,N - bis - (2 - hydroxyethyl) lauramide, H,N-bis-(2-hydroxyethyl) capramide, N1N-bis-(2-hyroxyethyl) myristamide, N,N-bis-(2, 3-dihydroxypropyl) lauramide, N,N-bis-(2, 3-dihydroxypropyl) myristamide, N,N-bis-(3-hydroxypropyl) lauramide, N,N-bis- (3-hydroxypropyl) capramide, N,N-bis-(2-hydroxypropyl) myristamide and N,N - bis - (4-hydroxybutyl) lauramide.  Diethanolamide compounds are preferred. (For preparation of these dialkylolamides see Group IV (b)). Impurities such as soap, free alkylolamine and piperazine type derivatives may result as by-products during the manufacture of the dialkylolamides, and provided that these impurities are not present in such amounts as to interfere with the detergent action of the final composition, the dialkylolamide product containing them may be used without further purification. The sulphated or sulphonated detersive compound may be an aliphatic acylcontaining compound containing 8 to 22 carbon atoms in the acyl group such as the sulphated or sulphonated aliphatic carboxylic esters containing 10 to 26 carbon atoms in the molecule.  Other specified detergents include the sulphuric acid esters of polyhydric alcohols incompletely esterified with higher (i.e. at least 8 carbon atoms) fatty acids such as coconut oil monoglyceride monosulphate or tallow diglyceride monosulphate; pure or mixed higher alkyl sulphates such as lauryl sulphate, cetyl sulphate and fatty alcohol sulphates derived from reduced coconut oil fatty acids; the hydroxy sulphonated higher fatty acid esters such as the higher fatty acid esters of 2, 3-dihydroxypropane sulphonic acid; the higher fatty acid esters of lower alkylol sulphonic acids such as the oleic acid ester of isethionic acid; the higher fatty acid ethanolamide sulphates; and the higher fatty acid amides of amino alkyl sulphonic acids, e.g. lauric acid tauride.  The higher alkyl-aryl sulphonates may also be used.  The aromatic nucleus may be mononuclear or polynuclear in structure, and may be derived from benzene, toluene, xylene, phenol, cresols or naphthalene.  The alkyl substituent may be straight or branched-chain in structure; specified alkyl groups include decyl, dodecyl, keryl, pentadecyl, hexadecyl and mixed alkyl groups containing at least 8 carbon atoms derived from long-chain fatty materials, cracked paraffin wax olefins or polymers of olefins such as propylene tetramer.  The alkyl group may have 8 to 22 carbon atoms, and preferably 12-18.  The detergents may be used as their water-soluble amine, alkali-metal or alkaline-earth metal salts, preferably the alkylolamine (especially mono-, di- and triethanolamine) salts.  The ratio of dialkylolamide to anionic detergent may be between about 1 : 10 to about 2 : 1 by weight, preferably from about 1 : 7 to about 1 : 1 by weight.  Depending on the solvent power of the selected solvent, the amount of total solids in the composition may be from about 30 per cent. to about 90 per cent., preferably at least 40 per cent.  The amount of anionic detergent may be 40-60 per cent. and that of dialkylolamide 10-20 per cent.  The dialkylolamide may be incorporated in the detergent at any stage of the manufacturing process, but it is preferred to add the molten dialkylolamide to a warm water, aqueous alcohol or alcohol solution of the detergent or to dissolve the dialkylolamide in alcohol or water and add the so formed solution to the detergent. Further dilution to the desired concentration may be necessary. In an example (all parts by weight) 13 parts of lauric diethanolamide, 44.7 parts of the triethanolamine salt of dodecyl benzene sulphonate, 7.5 parts of triethanolamine sulphate, 22.3 parts of water and 12.5 parts of ethyl alcohol are mixed to form a detergent composition.

Reisaued June 15, 1954 UNITED STATES PATENT xOFFlCE zaam LIQUIDANIONIC-DIALKYLOLAMIDE DETERGENT COMPOSITION No Drawing. Original No.2,607,740, dated August 19, 1952, Serial No. 159,854, May 8, 1950.Application for reissue August 18, 1958, Serial 18 Claims.

Matter enclosed in heavy brackets I: J appears in the original patentbut forms no part of this reissue specification; matter printed initalics indicates the additions made by reissue.

The present invention relates to new liquid synthetic detergentcompositions and, more particularly, to compositions of the type of thewater soluble anionic sulfated and sulfonated detergents in the liquidstate having improved properties.

There has been a considerable amount of research to discover substancesor additives which aid the eiilciency of detergent compositions. Theproblem is exceedingly complex, however, in view of the variousphysico-chemical mechanisms or properties and the like involved in theaction of a detergent composition including suspension. interfacialtension, micellar structure, dispersion, foam stability, etc. and thegeneral dii'llculty usually in determining the particular mechanismwhich is being altered by changes in the fol-mu; lation of detergentcompositions.

During recent years, synthetic detergents of the type of the organicsulfates and suifonates have been developed which in general havecertain properties which render them more suitable than soaps forcertain uses. By virtue of the diverse nature of such syntheticdetergents in comparison to soap, and consequently the fact that theyhave extremely diflerent properties in aqueous solution, e. g. thenon-formation of insoluble precipitates in hard water, there has beenuncovered a large field for research and development. In general, theexploration for suitable additives or builders for synthetic detergentcompositions of the type of the anionic sulfates and sulfonates has beendirected by the require-' ments of increased foaming and/or detersivepower. While the exact relationship, if any, between foaming anddetergency is not known, it

is highly desirable that these detergent compositions exhibit excellentfoaming properties, in addition to a high level of detersive emciency.particularly for consumer appeal and certain home and industrial uses.In view of the complex nature of both the foam and detergency phenomena,the character of such non-soap synthetic detergents, and the many othervariables in detergent compositions, additives in general exhibit acertan degree of specificity of action.

In general, because of technical facility of manufacture and relativeease of solution in water, most of these synthetic detergents areproduced and sold in particulate form. Although generally moresatisfactory in the form of solid particles for many uses these productsdo have certain disadvantages. Among these are the presence of a certainproportion of fines which may be sufficient to be irritative as a dustnuisance, bulkiness, possible development of tackiness, caking,frangibiiity, etc.

The preparation of a suitable synthetic detergent compositlon in liquidform is however a specialty problem and beset with many difflcultiesunique with such a preparation. A few of the vital considerations areset forth below individually, but it is to be noted of course that thedevelopment of a suitable liquid detergent composition necessarilyinvolves an integration of the inter-relationship among such factors:

1. Viscosity.-The composition should be fluid to such an extent that itmay be pourable from a container with ease. In general, the anior'icsulfate and sulfonate detergents herein referred may be even solids atnormal temperatures. In the molten state, they are usually highlyviscous and tacky moreover.

2. Selective solvent-The liquid media which may be employed mustnecessarily be selective in action. It should be somewhat miscible orsoluble with water, render a high degree of fluidity to the composition,have solubilizing effects on the detergents, permit adequateconcentration of solids, etc.

3. Cloud point-Clear point.'1'he composition should have sufllcientlylow cloud and clear points that it does not upon subjection toreasonable adverse conditions, e. g. slight chilling, separate intodifferent phases or solidify, and does maintain preferably a high degreeof sparkle and clarity of solution.

4. Foaming-The compostion should yield a good volume of foam with a highdegree of foam stability during washing operations. The foam should beof good creaminess or consistency, not break down readily in thepresence of soil, etc.

5. Grease emulsiilcation.--It should possess the ability to emulsifyreadily fats, oils, greases and the like in order to facilitate removalof the same in washing operations, particularly dishwashing.

6. Soil removal.-The detersive eillciency is in large measure due to theamount of soil removed. The composition should exhibit a high level ofsoil removal power, particularly in washing of fine fabrics,dishwashing, and the like.

'7. Concentration-The composition should preferably possess suchsolubility characteristics that a concentrated solution may ordinarilybe prepared for use whereby a relatively small amount may beconveniently utilized by the consumer and yet be adequate for many uses.

8. Non-irritative.-The solution should be non-irritative to the generalpublic as much as acids of higher and lower molecular weight.

possible and possess a desirablefeel to the hands.

Other vital considerations will be apparent from the followingdescription.

It has now been discovered that the incorporation of dialkylolamides ofhigher fatty acids of about 10-14 carbon atoms in liquid syntheticdetergent compositions consisting essentially of the [anionic sulfatedand sulfonated detergents are] anionic higher alkyl aryl sulfonated andhigher alkyl sulfated detergents, as hereinafter described, areeffective to achieve a significant and synergistic enhancement insurfaceactive properties such as detergency and foaming. Moreparticularly, the present invention comprises a liquid detergentcomposition consisting essentially of the said water soluble anionicsulfated or sulfonated detersive salts, a proportion of capric, lauricor myristic dialkylolamide eflective to enhance the action of thedetergent composition in aqueous solution, and a solubilizing diluent.

The enhancing additives of the present invention are characterized bytheir weakly polar nature and may be represented by the formula:

wherein R-CO represents a fatty acyl radial of 10-14 carbon atoms, and Rand R" may be the same or different, each being a lower hydroxyalkylgroup of preferably up to about and, more particularly, from about 2 toabout 5 carbon atoms. The hydroxyalkyl groups may be monoor polyhydroxyalkyl. Examples of suitable additives are N,N bis (2) hydroxyethyl)lauramide, N,N bis (2 hydroxyethyl) myristamide, N,N bis (2Lydroxyethyl) capramide, N,N bis (2,3 dihydroxypropyl) lauramide, N,Nbis (2,3 dihydroxypropyl) myristamide, N,N bis (Ii-hydroxypropyl)lauramide. N,N bis (3 hydroxypropyl) capramide, N,N bis (2hydroxypropyl) myristamide, N,N bis (4 hydroxybutyl) lauramide, etc.Because of the excellent results obtained it is preferred to use thediethanolamide compounds and the additives possessing a fatty acylradical of 12-14 carbon atoms.

These dialkylolamides may be prepared in any suitable manner andnumerous processes for their production are well known in the art. Aconvenient and economical volves the condensation of the higher fattyacylating compounds (e. g. lauric acid, lauric acid halide, etc.) with asuitable amino compound to produce a reaction amide structure.

The higher fatty acylating substances may be derived from pure, impureor commercial grades of capric, lauric or myristic acids and the like.More particularly, these acids may be produced from fatty oils, fats,greases, and other natural sources or be of synthetic origin as derivedfrom the oxidation of hydrocarbons. According to its origin and thedegree and manner of purification, capric, lauric and myristic acids maybe commonly admixed or associated with other fatty It is within thescope of the invention that the capryl, lauroyl and myristoyl compoundsmay be associated with other fatty substances and the like provided thecharacter and amount of such other materials are not sufficient tosubstantially neu tralize or materially affect the enhancing power ofthe additives in the relationship set forth. Thus, there may be suitablyemployed for the mode of synthesis inproduct having the desiredpreparation of the dialkylolamide additives the commercially purecapric, lauric and myristic acids having a concentration of such acidsof about and above. A typical composition of commercially pure lauricacid may be 90% lauric acid, 9% myristic acid, 1% unsaturated acids,trace capric acid. Another suitable fatty acid mixture is topped coconutoil fatty acids produced by the removal of a low-boiling fraction, e. g.10-15%, from coconut oil fatty acids.

Among the dialkylolamines suitable for condensation are diethanolamine,N,N bis (2,3 dihydroxypropyl) amine, dipropanolamine', N,N, bis (2hydroxypropyl) amine, dibutanolamine, etc. It is to be understood thatthe dialkylolamines may be utilized in pure, impure, or commercial form.

According to the circumstances of manufacture of the dialkylolamide, itmay be chemically and/or physically associated with other materials suchas soap, free alkylolamine, piperazine type derivatives, etc. Thepresence of varying amounts of such materials and the like in admixturewith dialkylolamide is contemplated within the scope of the presentinvention, provided the same are not significant enough to materiallyneutralize or substantially adversely affect the desired improvements tobe accomplished with the combination of the anionic detergent and thedialkylolamide additive.

It is a particular feature of this invention that the reaction productof the higher fatty acylating substance and the dialkylolaminecomprising the desired dialkylolamide and other derivatives as producedunder certain conditions may be utilized with marked success asadditives in the novel compositions of the present invention. Moreparticularly, the product is to be produced by the condensation of thesuitable higher fatty acids or their equivalent with an equivalent or anexcess of dialkylolamine, the molar ratio being from about 1:1 to about1:10 but preferably up to about 1:5 and usually from about 1 :2 to about1:3, at from about C. to about 200 C., and preferably from about C. to180 C., and achieving a reaction mixture equilibrium comprising aneffective amount of the dialkylolamide. With the fatty acids, an excessof dialkylolamine will usually be used, preferably up to about 311.Using fatty acids or anhydrides illustratively as reactants, as thewater is distilled off or otherwise removed during the reaction, theacid number falls indicating formation of amides. The reaction is to becontinued until the desired amount of water has been removed, e. g. notsubstantially in excess of 15% acid or soap and preferably up to about10% as determined by the acid value resulting from titration of thereaction mixture with potassium hydroxide. With the use of methyl estersand the like as reactants. the amount of alcohol liberated is an indexof completion of the reaction. In the case of the acid chlorides and thelike as reactants, formation of chloride ion or its equivalent may bedetermined also. This condensation reaction between the higher fattyacids and the alkylolamines or their equivalents is highly complex andproduces a variety of products in addition to the desireddi-alkylolamide. Accordingly, it is necessary to achieve an equilibriumof the reaction mixture containing an effective proportion of thedialkylolamide. This equilibrium may be achieved usually by permittingthe reaction mixture to cool relatively slowly or maintaining thereaction mixture at slightly elevated temperatures for a sufficientperiod of time. The optimum equilibrium of the reaction mixture howeverachieved may be determined by routine tests such as hereinafter setforth wherein the novel liquid detergent compositions are subjected topractical washing operations. A typical suitable reaction mixture citedfor illustrative purposes and resulting from the condensation ofcommercially distilled lauric acid in 90% purity and commercialdiethanolamine contains the following components on a solids basis:diethanolamide about 65 diethanolamine soap about 10%, free amine,diethanolpiperazine and minor amounts of possibly other substancestotaling 25%. The reaction product may contain usually minor amounts ofwater also, e. g. about The novel compositions of the present inventioncontain as the active ingredient the [anionic sulfated and sulfcnateddetergents (in-] following anionic higher alkul aryl sulfonated andhigher alkyl sulfated detergents (including suitable mixtures thereof).[Included therein are the aliphatic sulfated or sulfonated agents, suchas the aliphatic acyl-containing compounds wherein the acyl radical hasabout 8 to about 22 carbon atoms, and more particularly, the aliphaticcarboxylic ester type, containing at least about 10 and preferably about12 to about 26 carbon atoms to the molecule. Among the aliphaticdetersive compounds, it is preferred to use the sulfated aliphaticcompounds having about. 12 to about 22 carbon atoms] [As suitable]Suitable examples of aliphatic detergents [may be found the sulfuricacid esters of polyhydric alcohols incompletely esterifled with higherfatty acids, e. g. coconut oil monoglyceride mono sulfate, tallowdiglyceride monosulfate;] are the long chain pure or mixed higher alkylsulfates e. g.] selected from the group consisting of lauryl sulfatecetyl sulfate] higher fatty alcohol sulfates derived from reducedcoconut oil fatty acids the hydroxy sulfonated higher fatty acid esters,e. g. higher fatty acid esters of 2,3 dihydroxy propane sulfonic acid;the higher fatty acid esters of low molecular weight alkylol sulfonicacids, e. g. oleic acid ester of isethionic acid; the higher fatty acidethanolamide sulfates; the higher fatty acid amides of amino alkylsulfonic acids, e. g. lauric amide of taurine, and the like].

[Within the ambit of the invention are the alkyl aryl sulfonatedetergents also.] The[se] aromatic sulfonate detergents are also knownin the art. There may be mononuclear or polynuclear in structure. Moreparticularly the aromatic nucleus may be derived from benzene, toluene,

xylene, phenol, cresols, naphthalene, etc. The alkyl substituent on thearomatic nucleus may vary widely, as long as the desired detergent powerof the active ingredient is preserved. While the number of sulfonic acidgroups present on the nucleus may vary it is usual to have one suchgroup present in order to preserve as much as possible a balance betweenthe hydrophilic and hydrophobic portions of the molecule.

More specific examples of suitable alkyl aromatic sulfonate detergentsare the higher alkyl aromatic sulfonates. The higher alkyl substituenton the aromatic nucleus may be branched or straight-chain in structure;it comprises moreover such groups as decyl, dodecyl, keryl, pentadecyl,[hexadecyl,] mixed long-chain alkyls derived from long-chain fattymaterials, cracked parailln wax oleilns, polymers of lower monooleflns,etc. Preferred examples of this class are the higher alkyl mononucleararyl sulfonateshigher alkyl sulfates, and

wherein the alkyl group is-[about 8 to about 22,] 8 to 15 carbon atoms.[and preferably about 12 to 18 carbon atoms] More particularly, it ispreferred to use the higher alkyl benzene sulfonates [wherein the higheralkyl group is about 12 to 16 carbon atoms]. For example, propylene maybe polymerized to the tetramer and condensed with benzene in thepresence of a Friedel-Crafts catalyst to yield essentially the dodecylbenzene derivative which is suitable for sulfonation to the desiredsulfonate compounds.

These various anionic detergents are to be used in the form of theirwater soluble salts such as the amine, alkali metal and alkaline earthmetal salts. while the sodium, potassium salts and the like may besuitably employed, it is preferred to use the ammonium, lithium, amineand alkylolmine salts in view of their generally greater solubility inaqueous solution. More particularly, it is preferred to use themonoethanolamine, diethanolamine, triethanolamine salts and mixturesthereof because of the excellent results attained with their useparticularly with the higher alkyl benzene sulfonates, the the higherfatty acid monoglycerides sulfates (and mixtures thereof) as the activeingredients].

Any suitable solvent may be employed as the liquid medium. It shouldpossess several essential characteristics since it functions necessarilyas an integral part of the composition. Beside its chemical inertness,it must have a solubilizing action on the solids. It should possess asubstantial solubility for the anionic detergent and the dialkylolamideadditive jointly; it should be water miscible or water soluble in viewof the fact that the present compositions are designed at least in partfor use in aqueous solutions; it should possess a relatively lowviscosity in order to impart to the composition proper fluidity; itshould preferably possess reasonably good stability to heat, light,chilling, etc. It has been found that a low molecular weighthydroxylcontaining solvent may be suitably employed. More particularly,a liquid solvent medium may be selected from the group consisting ofwater, low molecular weight alcohols and mixtures thereof. The alcoholsshould preferably be the saturated aliphatic type; they may be monoorpolyhydric in character, and may contain inert solubilizing groups suchas other linkages. Suitable examples are ethyl alcohol, n-propylalcohol, isopropyl alcohol, n-butyl alcohol. In comparison. to ethylalcohol and the like, the higher alcohols such as butanol and the likeare not preferred since the latter have in general a comparativelyundesirable odor and less solubillty in water. Additional suitablesolvents of the polyhydric alcohol type are ethylene glycol, propyleneglycol, glycerol, etc. Alcohols possessing ether linkages are monomethylether of ethylene glycol, monoethyl ether of ethylene glycol, diethyleneglycol, diethylene glycol monoethyl ether, monobutyl ether of diethyleneglycol, monomethyl ether of diethylene glycol, dioxan,

etc. It is preferred to use water, the aliphatic monohydric alcohols andthe dihydric alcohols of about 2 to about 4 carbon atoms, and the loweralkyl ethers of said dihydric alcohols, and mixtures thereof.

The dialkylolamide may be incorporated with the anionic detergent at anypoint during the manufacturing process at which subsequent operationswill not adversely modify the properties of the detergent compositions.Preferred procedures are the melting of the dialkylolamide and stirringit into a warm water, water and alcohol, or alcohol solution of thedetergent, or the dissolving of the additive in alcohol or water andstirring the mixture into the anionic detergent. Thereafter, the mixturemay be further diluted to desired concentrations if necessary.

The ratio of the dialkylolamide additive to the anionic detergentsshould be sufficient to effect the desired improvements in detersivecapacity and/or foaming power. The proportion is highly variabledepending upon the specific materials to be employed and will generallybe from about 1:10 to 2:1 by weight for improvement in foaming and fromabout 1:7 to about 2:1 for improvements in detersive power also. It ispreferred that the proportions be from about 1:7 to about 1:1 foroptimum effects usually.

The amount of solvent should be sufdcient to dissolve and liquefy thesolid components. The amount of total solids in such liquid compositionsis variable and is limited chiefly by the degree of solubility in theliquid medium. For optimum effects, the amount of total solids should befrom about 30% to about 90% depending upon the solvent power, andpreferably at least about 40%. More particularly, it is preferred thatthe anionic detergent be at least about 30%, and generally from about40-60%, with the concentration of dialkylolamide usually at least aboutand preferably from about 10 to about Where these solids are notsuiliciently soluble in water alone for example, their solubility may beappropriately improved by the use of a mixed solvent medium, e. g. waterand ethyl alcohol. While it is preferred to prepare these compositionsin the form of a concentrated solution as indicated above whereby theconsumer may utilize the same conveniently and economically, it iswithin the scope of the invention that these compositions may be furtherdiluted and be useful for many purposes, e. g. window, walls, woodwork,car washing, etc.

The following data and examples are additionally illustrative of thenature of the invention and it will be understood that the invention isnot limited thereto.

From the viewpoint of foaming generally, the novel compositions of thepresent invention are characterized by increased stability of the foamproduced in washing operations in comparison to the foaming effectsproduced by the compositions without the dialkylolamide. The foam of thecompositions containing an anionic-dialkylolamide oombination have goodcreaminess and consistency, do not readily break down by evaporation,have in general a long drainage time and contain an increased amount ofliquid.

It has also been found that this combination tends to increase thetolerance of the detergent composition for the assimilation or holdingin suspension of a miximum amount of dirt, grease, etc. with less foamloss than is found without the use of the dialkylolamide additives.

In practical dish pan tests wherein a small amount of the liquiddetergent is added to a dishpan of water and greased dishes are washedby hand, it can be shown that the anionic detergentdialkylolamidecombination exhibits superior foaming properties. As increasing numbersof greased plates are washed the foam decreases. The rate of foamdecrease is considerably slower on solutions of the compositions of thepresent invention than with corresponding solutions of the anionicdetergent or dialkylolamide alone.

Moreover, the present compositions exhibit high emulsiflcation power onthe fats, oils, and other greases normally adhering to dishes.

Table I discloses comparatively the results in foam endurance orduration obtained in the dishwashing of greased plates with threecompositions. Composition I contains 52 parts anionic active ingredientconsisting essentially of the triethanolamine salt of dodecyl benzenesulfonate with a minor amount of triethanolamine sulfate.

and 48 parts solvent consisting of water and ethyl alcohol mixture.Composition II consists of 13 parts lauroyl diethanolamide with the samediluent as the remainder. Composition III contains the desiredcombination of I and 11, namely 52 parts anionic active ingredient, 13parts lauroyl diethanolamide, and the remainder being the water-ethylalcohol solvent. The tests are conducted in soft water at 115 F. withthe number of greased plates washed by the anionic detergent alone(composition I) before expiration of the foam being taken as a standardof The results with compositions II and III are tabulated in terms ofpercent of the standard.

Table I Foam En- Composition s Per Cent 1 'lriethanolamine salt ofdodecyl benzene sulfonutc (52 parts) 100 II Lauroyl dicthanolamidc (13parts) 69 III 'Iriethanolamine salt of dodecyl benzene sulionate (52parts) +lsuroyl diethanolamide (13 parts). 212. 5

The unusual effects obtained'by the compositions of the presentinvention (e. g. composition III) is evident from the data. It is clearthat the combination achieves a synergistic enhancement in foam durationand resistance to greasy soil in comparison to the effects obtained bythe individual use of identical amounts of the components.

It may be added moreover, that the combina tion gave a high volume offoam of good consistency and relatively small bubbles. The anionicsynthetic detergent alone gave a satisfactory volume of foam but ofquite light consistency and composed of relatively large bubbles. Thedialkylolamide exhibits a relatively poor volume of foam which is alsoof light consistency and large bubbles.

The grease adhering to the dishes appeared to be duration of washingwith the anionic detergent alone and with the anionic-dialkylolamidecombination. The fact must be noted however that over twice as manygreased dishes were washed by the combination in the above relationship.On the other hand. the grease was unsatisfactorily emulsified using thedialkylolamide alone after only a very minor proportion of dishes werewashed.

Table II indicates the results obtained in similar dishwashingoperations in hard water (300 p. p. m.) at F. of Composition III abovecontaining the anionic detergent-dialkylolamide combination incomparison to a standard detergent composition consisting of a 60%solution of the same anionic detergent. The dishwashing operations werecontinued until both the foam had expired and unemulsified greaseappeared on the surfaces of the washed dishes. The data is set forth asthe percent improvement achieved satisfactorily emulsified and removedfor the using the combination in comparison to the effects encounteredusing the anionic detergent alone as a standard.

Table II Percent Improvement in grease emulsiflcation usinganionic-dialkylolamide combination 16'! Improvement in foam enduranceusing anionic-dialkylolamide combination 100 The unusual resultseffected by the combination is evident from the data. The fact that thetesting conditions were severe (water of 300 p. p. m. hardness) and thatthe standard composition contains 60% anionic detergent in comparison tothe use of 52% in the novel compositions renders the results all themore striking.

In addition, the liquid detergent composition containing the combinationindicated above exhibits a cloud point of as low as approximately mentsin soft water with palmitoyl-diethanolamide in combination with the sameanionic detergent as used above in a 1:10 and 2:10 ratio by weightdiscloses that the foam volume and its stability or resistance to greasysoil is consistently poorer than the effects obtained by use of theanionic detergent alone.

In addition, the effects on the foaming characteristics can be studiedquantitatively for a given composition by means of a foam consistencytest. Briefly, this test consists of the formation of a foam bystandardized agitation of 500 cc. of a detergent at 110 F. in a twoquart unsilvered Dewar flask. The foam formed after a minutes agitationperiod is then measured with a consistometer after standing for 5, 10and minutes. The readings are an indication of the foam consistency orbodying effect. On a comparative basis, higher readings representimproved consistency or body of the foam.

This consistometer is a means for measuring the minimum torque necessaryfor rotation of a paddle of any standard size through a foam. Thisdevice applies the torque by means of a coil spring which has its innerend attached to a paddle shaft and the outer end attached to a circularplate which can be rotated. The degrees through which the spring may betwisted before the paddle starts to move in the foam may be readilydetermined. An indicator needle is attached to the top of the paddleshaft and a circular scale divided into 360 is set on the plate whichholds the outer end of the spring. The paddle shaft is held in place bya pair of ball bearing races in such a way that it can turn freely.

Comparative foam consistency tests are conducted in distilled waterusing as a standard triethanolamine salt of dodecyl benzene sulfonate incomparison to a detergent composition consisting of a mixture of thesulfonate salt andv 75 10 lauroyl diethanolamide, the ratio of anionicdetergent to dlethanolamide being 6.66 to 1. The results are set forthin Table III, the consistometer readings representing the averages at 5,

It is evident from the data that the mixed anionic dialkylolamidedetergent composition yields a high level of creaminess and foamstability in comparison to the relatively flimsy sudsing power exhibitedby the anionic detergent alone.

The effect on detergency on compositions of the present invention may beindicated by a standard soil removal test. This testing procedureinvolves the uniform soiling, washing with particular detergentcompositions in distilled water at E12 F. and drying of a large numberof woolen swatches. The whiteness of the various test swatches aremeasured by a Hunter reflectometer. The units of soil removed may becalculated by subtracting the average reflectivity of unwashed controlsamples from that of the washed swatches.

Table IV indicates the percent improvement in soil removal on woolswatches using the detergent composition comprising 52% anionicdetergent consisting essentially of the triethanolamine salt ofdodecylbenzene sulfonate, 13% lauroyl diethanolamide, and 35% diluentconsisting of a water and ethyl alcohol mixture, in comparison to thestandard detergent composition consisting of a 60% solution of the sameanionic detergent without added dialkylolamide at various indicatedtotal concentrations of the detergent compositions in distilled water.

The synergistic improvement in detergency resulting from the use of themixed anionic-dialkylolamide combination is graphically evident from thedata.

Example I An improved liquid synthetic detergent composition is preparedby mixing 13 parts of lauroyl diethanolamide, an anionic detergent basecontaining 44.? parts triethanolamine salt of dodecyl benzene sulfonateand 7.5 parts triethanolamine sulfate, 22.3 parts water and 12.5 partsethyl alcohol.

Example II The composition of Example I is reproduced Example III Thecomposition of Example I is reproduced using the triethanolamine salt oflauryl sulfate .as the anionic detergent.

Example IV An improved liquid synthetic detergent composition isprepared by mixing the ingredients of Example I with the modificationthat a fatty acid-diethanolamine reaction mixture prepared as follows issubstituted for the lauroyl diethanolamide. Topped coconut oil fattyacids are reacted with commercial diethanolamine in a 1:2 ratio at about150 C. until the acid value drops to about 10. The reaction mixture isfinished by a slow cooling process which involves cooling the mixturewith water at 120 F. circulating in a Jacket, the mixture being agitatedduring this time. When the mixture reaches about 120 F.. the agitationis stopped and the mixture allowed to stand overnight during which timefurther slow cooling takes place.

Example V The process of Example III is repeated with the modificationthat the dialkylolamide reaction mixture is made in accordance with thefollow procedure. Commercial lauric acid is melted and commercialdiethanolamine is added with agitation till a 1:2 molar ratio isreached. The reaction mixture is heated at 140-160 C. under vacuum. Atthis temperature, distillation of water occurs until the acid or soapcontent has been reduced to a value equivalent to 4.35%. calculated asdiethanolamine laurate. The reaction product is rapidly run out of thereactor with cooling and permitted to cool gradually.

The following formulations are also productive of a high level offoaming and detersive properties:

Example VI Per cent Triethanolamine salt of lauryl sulfate 25Triethanolamine salt of dodecyl benzene sulfonate 25 N,N bis (2,3dihydroxypropyl) myristamide 15 Water 15 Ethyl alcohol 20 [Example VII][Per cent] [Ammonium salt of higher fatty acid monoglyceride sulfatesderived from coconut Monoethanolamine salt of higher fatty acidmonoglyceride sulfates derived from coconut oil Lauroyl diethanolamide12 Water 13 Monomethyl ether of ethylene glycol 20 12 Example [IX] VIIIPer cent Trizthanolamine salt of kerylbenzene sulfon- Commercial lauroylacid diethanolamide condensate containing 65% diethanolamide, 10% soap,25% diethanolamine andbyproducts 31 Water 17 Monoethyl ether ofdiethylene glycol 7 [Ebrample X] [Per cent] [Higher fatty acid amides oftaurine derived from coconut oil-triethanolamine salt 40 Capryl andlauroyl diethanolamide (l 1) 20 Water l5 Ethyl alcohol 25] The termconsisting essentially of as used in the definition of the ingredientspresent in the composition claimed is intended to exclude the presenceof other materials in such amounts as to interfere substantially withthe properties and characteristics possessed by the composition setforth but to p rmit the presence of ther materials in such amounts asnot substantially to afi'ect said properties and characteristicsadversely.

Although the present invention has been described with reference toparticular embodiments and examples, it will be apparent to thoseskilled in the art that variations and modification can be substitutedtherefor without departing from the principles and true spirit of theinvention.

Having described the invention what is desired to be secured by lettersPatent is:

1. A concentrated liquid detergent composition having a high level ofperformance in dishwashing consisting essentially of water-soluble[detergent selected from the class consistin of water-soluble salts ofanionic sulfated and sulfonated detergents having a long aliphatic chainof 8 to 22] anionic salt of alkyl aryl sulfonate detergent, said alkylgroup having 8 to 15 carresented by the formula;

wherein R-CO- is a fatty acyl radical of 10 to 14 carbon atoms, and Rand R" are hydroxyalkyl groups of up to about 5 carbon atoms each, theratio of said dialkylolamide compound to anionic detergent being fromabout 1:10 to about 2:1 by weight, and said dialkylolamide and anionicdetergent together being at least about 30% by weight in a selectiveliquid solvent therefor.

2. A concentrated liquid detergent composition having a high level 0!performance in dishwashing consistin essentially of water-soluble saltof higher alkyl mononuclear aryl sulfonate deter- Eent, said higheralkyl group having 8 to [22] 15 carbon atoms, and, a dialkylolamidecompound anionic detergent being from about 1: 10.to about 2:1 byweight, and said dialkylolamide and anionic detergent together being atleast about 30% by weight in a selective liquid solvent therefor.

3. A concentrated liquid detergent composition having a high level ofperformance in dishwashing consisting essentially of water-soluble saltof higher alkyl benzene sulfonate detergent, said higher alkyl grouphaving 8 to [22] 15 carbon atoms, and a diethanolamide compoundrepresented by the formula:

R-CO-N-(CHaCI-IaOH) 2 wherein RCO is a saturated fatty acyl radical of10 to 14 carbon atoms, the ratio of said diethanolamide compound toanionic detergent being from about 1:10 to about 2:1 by weight. and saiddiethanolamide and anionic deter nt together being at least about 40% byweight in a selective liquid solvent therefor.

4. A concentrated liquid detergent composition having a high level ofperformance in dishwashing consisting essentially of anionic [detergentselected from the class consisting of water-soluble salts of anionicsulfated and sulfonated detergents having a long aliphatic chain of 8 to22] water-soluble salt of alkgl benzene sulfonate detergent, said alkglgroup having 8 to 15 carbon atoms, and a dialkylolamide compoundrepresented by the formula:

wherein R-CO is a fatty acyl radical of 10 to 14 carbon atoms, and R andR" are hydroxyalkyl groups of up to about carbon atoms each, the ratioof said diailrylolamide compound to anionic detergent being from about1:10 to about 2:1 by weight, and said dialkylolamide and anionicdetergent together being at least about 30% by weight in a selectiveliquid solvent therefor comprising a low molecular weight aliphaticalcohol.

5. A concentrated liquid detergent composition in accordance with claim4 wherein the fatty acyl radical is lauroyl and the hydronvalkyl groupshave 2 to 3 carbon atoms each.

6. A concentrated liquid detergent composition in accordance with claim4 wherein the fatty acyl radical is myristoyl and the hy-droxyalkylgroups have 2 to 3 carbon atoms each.

'7. A concentrated liquid detergent composition having a high level ofperformance in dishwashing consisting essentially of anionic [detergentselected from the class consisting of water-soluble salt of anionicsulfated and sulfonated detergents having a long aliphatic chain of 8 to22] water-soluble salt of alkgl mononuclear argl sullonate detergent,said alkgl group having 8 to 15 carbon atoms, and a diethanolamidecompound represented by the formula:

wherein RCO is a saturated fatty acyl radical of 10 to 14 carbon atoms,the ratio of said diethanolamide compound to anionic detergent beingfrom about 1:10 to about 2:1 by weight, and said diethanolamide andanionic detergent together being at least about 40% by weight in aselective liquid solvent therefor comprising a low molecular weightaliphatic alcohol.

8. A concentrated liquid detergent composition in accordance with claim7 wherein said solvent comprises an alcohol selected from the groupconsisting of aliphatic monohydric and dihydric wherein R-CO- is asaturated fatty acyl radical of 10 to 14 carbon atoms, the ratio of saiddiethanolamide compound to anionic detergent being from about 1:10 toabout 2:1 by weight, and said diethanolamide and anionic detergenttogether being at least about 40% by weight in a selective liquidsolvent therefor comprising a low molecular weight aliphatic alcohol.

10. A concentrated liquid detergent composition having a high level ofperformance in dishwashing consisting essentially of a solution of amixture of anionic [detergent selected from the class consisting ofwater-soluble salts of anionic sulfated and sulfonated detergents havinga long aliphatic chain of 8 to 22 carbon atoms, and a] water-solublesalt of alkgl benzene sulfonate detergent, said alkgl group having 8 to15 carbon atoms, and a dialkylolamide compound represented by theformula:

wherein R-CO- is a saturated fatty acyl radical of 10 to 14 carbonatoms, and R and R" are hydroxyalkyl groups of up to about 5 carbonatoms each, the ratio of said dialkylolamide compound to anionicdetergent being from about 1:7 to about 1:1 by weight, and saiddialkylolamide and anionic detergent together being at least about 30%by weight in a selective liquid solvent phase therefor comprising waterand an aliphatic saturated lower monohydric alcohol.

11. A concentrated liquid detergent composition having a high level ofperformance in dishwashing consisting essentially of a solution of amixture of anionic [detergent selected from the class consisting ofwater-soluble salts of anionic sulfated and sulfonated detergents havinga long] water-soluble salt of alkgl mononuclear arill sulfonatedetergent, said alkgl group having [allphatic chain of] 8 to [22] 15carbon atoms, and a diethanolamide compound represented by the formula:

wherein RCO is a saturated fatty acyl radical of 10 to 14 carbon atoms,the ratio of said diethanolamide compound to anionic detergent beingfrom about 1:10 to about 2 :1 by weight, and said diethanolamide andanionic detergent together being at least about 40% by weight in aselective liquid solvent phase therefor comprising water and analiphatic saturated lower monohydric alcohol mixture.

12. A concentrated liquid detergent solution in accordance with claim 11wherein said anionic detergent is essentially water-soluble-higher alkylbenzene sulfonate salt.

[13. A concentrated liquid detergent solution in accordance with claim11 wherein said anionic ethanolaniine salt 15 detergent is essentiallywater-soluble higher alkyl sulfate salt] 14. A concentrated liquiddetergent solution in accordance with claim 11 wherein saiddiethanolamide is at least about 10 by weight.

15. A concentrated liquid detergent solution in accordance with claim 11wherein said alcohol is ethyl alcohol. ,:i

16. A concentrated liquid detergents olution in accordance with claim 11which contains sodium salt of said water-soluble anionic detergent.

17. A concentrated liquiddetergent solution in accordance with claim 11which contains an of said water-soluble anionic detergent. I

18. A concentrated liquid detergentsoiution in accordance with claim 11which contains ammonium salt of said water-soluble anionic detergent.

19. A concentrated liquid detergent composition consisting essentiallyof a solution of a mixture of anionic water-soluble salt of higher alkyl16 sulfate detergent selected from the group consisting of launllsulfate and coconut fatty alcohol sulfate detergents, and adiethanolamide compound represented by the formula:

References Cited in the file of this patent or the original patentUNITED STATES PA'I'ENTS Number Name Date 2,173,448 Katzman Sept. 19,1939 2,383,737 Richardson Aug. 28, 1945

